FBI agents are not paid in hourly wages, they are paid through the federal government system GS ratings which provides agents an annual salary rating for years served.
The tariff of the United States, like all actual protective tariffs, is partly revenue and partly protective, its original purpose of yielding revenue having been subordinated to that of giving protection, until it may now be best described as a protective tariff yielding incidental revenue.
Thus the prime purpose of taxation is believed to be revenue. The money that is raised from various taxes is spent by the government for the construction of schools, roads, hospitals and also for other development causes. The national government also spends the earned revenue for the justice system and regulation.